Authorities in southeast Texas have launched an investigation after city workers found razor blades embedded in playground equipment at two parks.

Officials in Huntsville, located about 70 miles north of Houston, found four blades on two slides at Emancipation and Boettcher Mill Road parks.

Investigators told FOX 26 Houston a heating device is being used to melt portions of the plastic slides, and razor blades are then inserted into the melted surface.

City workers discovered the razors during an inspection on July 6 of the playground equipment. It’s not clear if children had used the slides prior to the discovery of the blades, but there were no reports of injuries.

A neighbor who lives near the park told FOX 26 Houston he was shocked to hear about the vandalism.

“It’s a shame kids can’t basically come out here and have fun without being in danger,” George Perry told FOX 26.

City officials are now installing surveillance cameras at the parks to help prevent a recurrence and help identify suspects.